Do Tubular Skylights Work On Cloudy Days?

Tubular SkylightToday, interest in renewable energy prompts many property owners to consider installing tubular skylights to infuse living environments with more natural light. These compact, affordable systems differ significantly from traditional skylights. They furnish some distinct advantages, yet also provide fluctuating levels of light in some places, unless owners take steps to include hybrid lighting systems also.

Traditional Skylights And Tubular Skylights

Traditional skylights essentially function as additional windows installed in roofs to admit more light into a structure. They offer the advantage of inexpensive renewable solar lighting, because the addition of sunlight via a skylight usually means a resident can use less interior electric lighting during the day, according to the Consumer Energy Center. Some disadvantages of skylights include:

  • Large skylights may prove bulky and require additional framing to install overhead
  • Heavy snowfall may cover skylights part of the year
  • Leaks may develop around skylight flashing

Partly to address some of these concerns, modern tubular skylights developed as an attractive alternative in some locales. These compact devices typically require a considerably smaller aperture in the roof for installation. According to Bob Vila, They usually consist of three components: a transparent curving dome; a tube and a light diffusion system. The cap functions as a lens to receive sunlight, which is then sent downwards through the tube into the residence. Along the way, a diffuser system helps transmit the natural light so it reaches its final destination.

Types of Tubular Skylights

Tubular skylights generally fall into two broad categories: transparent solid tubes which transmit light completely internally and hollow tubes that reflect light through reflective surfaces coating the lining of the tube, according to Bob Vila. Both varieties will diffuse natural light for short distances.

Both kinds of tubular skylights offer some benefits. These include:

  • Smaller roof apertures than traditional skylights provide
  • Typically tubular skylights prove easier to place because the tube will bend around pipes or framing timbers
  • They tend to weigh less than traditional skylights, and are therefore easier to maneuver
  • Some tubular skylights arrive from the factory with flashing in place, ready to attach to the roof

The federal government offers Energy Star ratings to these fixtures, just like windows. On the negative side, tubular skylights may not supply as much light as traditional skylights during colder winter months and they won’t allow a resident to see the stars at night, or admire a daytime sky. Additionally, the type of lens may significantly impact the quality of natural light transmitted indoors.

Operating During Cloudy Days

Just like other skylights, tubular skylights alone offer variable levels of indoor natural lighting. At night or during cloudy, overcast weather they admit significantly less light unless a property owner installs a hybrid unit including an artificial light source to maintain constant illumination. Some manufacturers supply units with LED lighting in place, for instance.

Related Resource: Types of Skylight Glass


A number of manufacturers offer tubular skylights today. They remain a popular option for adding exterior light to many interior locations.